Thank you all for response, yes I believe this seems to be a bit over the top in terms of issues to worry about, as indicated by your response above most of the effects would be localized more to the SRV. The posted MDMT on the vessel is -20F, but thats not really correct when you do the...
Strange question....one of my clients is being questioned by the AI with regard to whether the vessel MDMT reflects the low temperature which may result locally in the shell and nozzle in the event of a SRV opening, somebody (not I) has done calculations showing that theoretically the SRV...
Pretty much the conclusion I came to as well...most I talk to try avoiding it by skating through with a combination of UCS-66(g) and UCS-67(a)(3) as you indicated. Just seems kind of odd arguing to exempt the weld procedure from impact testing on one hand yet you always make sure your WPS has...
Do you have to do Production Weld impact test if you: A)Have ordered your material already impact tested (yes it is required to meet the MDMT) B)Have qualified Section IX weld procedures which includes impact testing well below the current MDMT and further includes PWHT
Basically I have a thick...
TGS4
That is a good point, I agree there are situations where stout is certainly not the best approach (cost has generally not been an issue at least in the instances I mentioned). Anyway what I take from this thread is that aside from leakage issues (and potentially stress sensitive areas)...
YP3135 - note G5 is the only guidance provided and it is clear on these points I was generally inquiring whether anybody had other situations where they would use the low stress
TGS4 - Other situations where I have used the low stress values over the high stress values are situations for...
Agreed. Aside from flanges assemblies etc, I have generally considered under what conditions the vessel is going to spend most of its operating life in determining which set of values to use.
This probably has been posted before.....I note the Code doesnt really doesnt provide much guidance with regard to when you use the high or the low allowable stress values for 316 and 316L SS, aside from advising you to use your best engineering judgement and to consider the lower values when...
jtseng123
I agree on all points you make, I guess the extra thickness thing is the argument for doing a higher hydro and sleeping better. I can safely say that in our local area I or anybody I have talked to (AIs included) have never been asked to design (in my 25 years) off anything other...
I agree that anytime you test above 1.3 x MAWP that you need to check against yield strength and the MAP calcs are good for that.
But I guess I would argue that designing off the MAWP is more conservative than designing off the MAP (and when I say MAWP the number used to start with is based on...
Hi Mike
Dont you find when you use that feature in Compress its annoying, if I dont shut it off it seems to generate about 3x the amount of paper than a similar calc done under APV
R
Hi
I am with you Gr2vessels,not sure what the overall benefit is, unless you are trying to increase the MAWP of the vessel after the fact (particularly low pressure vessels there could be a notable amount of excess material)...which I guess is perhaps what vesselfab is getting at.
So my...
Interesting looking a the definition they mention in 3-2, as directed there from UG-99(c) it reads for calculated test pressure: "The basis for calculated test pressure is the highest permissible design pressure as determined by the design formula for each element of the vessel using nominal...
Yes, but I did notice that in Para UG-99(c)(which admittedly I dont think I have ever really read in vengeance) it does indicate that you can test to the least MAP if you wish... given agreement between Owner, Fabricator and AI...but I dont really see what the benefit would be or what you would...
Hi
Hopefully there is a straight forward answer to this, I recently had a client indicate that with vessels which have extra thickness (ie I assume due to larger corrosion allowances (3/16' - 1/4") or I suppose cases where the nominal plate thickness used is "notably" thicker than the minimum...
I have had a closer look at the flanges in question and they are German and stamped EN 1092-1, and as noted above they are notably thinner than the 150# ASME flanges located adjacent to them. Fortunately the design pressure in this part of the system is 45 psig and the flanges have a 10 Bar...
No offense taken, my first post was a bit misleading with DIN in the wording (the components in the system are from Germany so out of prior habit I refer to them as DIN but they correctly termed European (metric) flanges) and I wasnt clear with respect to why I was doing it this way.
Yes I have...
I should add that I do see the irony in the fact that even ASME standard B16.5 flanges will not always meet the thickness requirements for a given pressure rating when subject to ASME calculation
I understand exactly what the DN and PN numbers stand for and the difference with regard to DIN (although in the past you could end up with DIN standard flanges on some German supplied piping and pressure equipment...probably dating myself with that one) . The problem is not all North American...
